1. Field of the Invention
This invention relates generally to hand operated wrench particularly to a universal multi-socket ratchet wrench wherein an adjustable hexagonal socket is adaptable to any hexagonal nuts or other bolt type fastener for tightening and loosening operations.
2. Description of the Prior Art
Conventionally, hand operated wrench for tightening and loosening hexagonal nuts includes open end wrench, box wrench, adjustable wrench and socket wrench, of which socket wrench requires a set of sockets in various specifications for taking replacement according to the size of nuts or other bolt type fasteners. The open end wrench has a major defect in its structure because during operation, the torsion from the wrench is only applied to the opposing two points of a quardrangle or hexagonal bolt head or nut, often resulting in either hurting the user from an accidental disengagement between the wrench and the workpiece or damaging the bolt head or nut. Although the box wrench has partially solved the problem yet it still has its limit similar to that of the open-end wrench, i.e. the workpiece must protrude out of the main body thereof. Besides, both the open end wrench and the box wrench have to be separately prepared in different sizes in conjunction with the different sizes of the bolt heads and nuts. Accordingly, an adjustable wrench and socket wrench are produced to meet the requirement. However, the adjustable wrench has the same defect as that of the open end wrench in torsion application, and the socket wrench has to separately prepare a plurality of different sockets according to the different specifications of bolts and nuts. In general, the prior art wrenches have the following problems, in which:
(1) Different sockets have to be prepared for replacement selection according to the requirement of different size of bolts and nuts, making the operations inconvenient and time consuming as well;
(2) As different specifications of the bolt and nut have to be adapted in manufacturing different wrenches and/or sockets, not only more materials are required but also more costs and working time are mounted accordingly; and
(3) In order to carry different components of the wrench, a larger tool case is required, making the carrying inconvenient to the user.